The First Benzo[1,2:4,5]dicyclobutenones and Their Tricarbonylchromium Complexes
作者:Ismail Abdelshafy Abdelhamid、Osama Mahmoud Ali Habib、Holger Butenschön
DOI:10.1002/ejoc.201100551
日期:2011.7.8
separation and acetal hydrolysis the title compounds 15 and 16 were obtained in high yields as the first representatives of their class. Complexation of the acetals with Cr(CO)6 gave the corresponding tricarbonylchromiumcomplexes in excellent yields. Subsequent deacetalization afforded the diketone complexes 18 and rac-20, which underwent stereoselective nucleophilic diadditions at –78 °C.
Thermal <i>Hetero</i>-Diels–Alder Reaction of Benzocyclobutenones with Isatins To Form 2-Oxindole Spirolactones
作者:Thomas Wurm、Ben W. H. Turnbull、Brett R. Ambler、Michael J. Krische
DOI:10.1021/acs.joc.7b02769
日期:2017.12.15
or “ortho-quinoid ketene methides”, which engage in intermolecular [4+2] cycloadditions with isatins 2a–2f to form 2-oxindole spirolactones 3a–3l. This process tolerates an array of different functional groups and substitution patterns, and is applicable to unprotected isatins 2b–2f bearing free NH-functionalities. The superior performance of isatins compared to other carbonyl based dienophiles was